No one likes steam these days because it's old and difficult to install correctly or modify later, but steam has some really cool features.
First, it doesn't require a pump to circulate. That means both the mechanical reliability of not having the electric motor and rotating water seal, or any moving part at all(1), but also you don't need any electricity.
It doesn't even need the usual low voltage circuit for the thermostat and gas valve. These are not common but also not new, there are millivolt systems where the thermostat & gas valve run only on the electricity generated by the thermocouple on the pilot.
It means that when ice has taken down all the power lines in a region, and blocked all the roads for repair crews to fix them at the same time, your heat stays fully working. No air blower, no water pump, not even 24v for the thermostat, and not by dint of having a ups which is just more stuff to fail.
Same goes for the hot water and the stove but that's more about gas than steam.
There is no getting around the huge efficiency of heat pumps of course. It just still kills me that we are accepting it as normal to require TSMC and ASML $billion chip fab infrastructure to make heat. But I guess you could say the same about leds and light so whatever I'm not saying we shouldn't use heat pumps.
(1) there is a moving part in the vent that opens and closes on each radiator, but that is a quality of life and longevity thing. If the vent fails to close or seal, the radiator still works, you still have heat, it just makes a hissing noise and consumes more fresh water which corrodes the boiler faster so it may leak in 5-10 years instead of 20-never.